This is a great article. Not to take anything away from the OP (just upvoted the post actually), but just out of curiosity I wonder why it is posted on HN. Is there certain range of topic the HN expect?
There's such a thing as a substantive anecdote, and self-observation and self-experimentation have a long and noble history. It's wrong, of course, to draw hard scientific conclusions from such a piece, but it's not wrong to read one, nor to write one, nor to do this kind of experimentation, nor to find it interesting. Plus there's a hacker angle in the DIY aspect.
That's my take on it, anyway. I thought it was cool, and I hope that HN readers are smart enough not to draw the obvious bogus conclusions.
Basically, xkcd 386.